Hello. I have a question I'm hoping you could answer. Yesterday, I installed a new toilet for my daughters bathroom. In the process of removing the old toilet, I noticed that the floor did not have a concrete/cement base for the new flange and toilet to properly be mounted without the toilet shaking slightly so I used a shim to help stabilize it better, which it helped. My question is, have you experienced situations where there were no concrete base to drill the flange to the floor and should I be concerned with the toilet tipping over even though I used sandstone grout around the base to create a better seal and to add more stability? Please keep in mid that I live in a block home (61') that apparently forgot to add concreye around the base but has concrete every where else.